Clutch for punch presses



June 4-, 1935. E. J. DREIS 2,003,529

CLUTCH FOR PUNCH PRESSES Filed June 22, 1951 2 Sheets-Shet 1 jag .11

INVENTOR.

A TTORNEYS.

June 4, 1935. J s

CLUTCH 1 6R PUNCH PRESSES Filed 'June 22, 1951 2 Sheets-Sheet 2 IAgE/YOR.

j f f PM ATTORNEYS.

Patented June 4, 1935 CLUTCH FOR PUNCH PRESSES Edward J. Dreis, San Francisco, Calif.

Application June 22, 1931, Serial No. 545,935

1 Claim.

This invention relates to punch presses and similar machines and particularly pertains to a clutch mechanism therefor.

It is the principal object of the present invention to provide a simple clutch of the characthereof is a locking dog I1.

ter referred to which will automatically and positively disengage at the end of each revolution of the driven member of the clutch.

In carrying the invention into practice, I provide a driving and a driven member associated with which is an operative clutch dog which normally tends to form a driving connection therebetween. This dog is automatically moved and held in inoperative position at the end of each revolution of the driven member and can be again rendered effective only by the operator releasing it through the medium of the control mechanism.

One form which the invention may assume is exemplified in the following description and illustrated by way of example in the accompanying drawings, in which:

Fig. 1 is a view of my improved clutch mechanism with parts in section to show certain features of construction.

Fig. 2 is a central longitudinal section through my improved clutch mechanism.

Fig. 3 is a transverse sectional view through the clutch showing the dog release mechanism in one position, the section being taken on line IIIIII of Fig. 1.

Fig. 4 is a View similar to Fig. 3 but showing the release mechanism in another position, the section being taken on line IVIV of Fig. 1.

Referring more particularly to the accompanying drawings, Ill indicates a clutch mechanism for punch presses or similar machines, which clutch mechanism is automatically rendered ineiiective each time the driven shaft makes one revolution.

In the drawings II indicates the hub of a flywheel or other driving member which revolves concentricallyto a driven shaft I2. This'may bethe crank shaft of a punch press or any other driven member which it is desired to operate. The shaft I2 as herein shown is provided with a reduced pilot member I4 engaging a bearing I5 in the end of the hub II.

Mounted on the driven shaft I2 and suitably keyed thereto is a sleeve I6. Mounted in a suitable guide in this sleeve for movement coaxially This locking dog I! is positioned in a radial position where its inner surface bears on the outer periphery of the shaft I2. Disposed in a similar radial position is a socket I8 formed in the end of the hub II, which socket is adapted to register with the inner end of the locking dog I'I so that the latter may project therein. Acompression spring I9 is interposed between the outer end of the locking dog I1 and a stationary collar 20 on the shaft I2, which spring normally tends to urge the locking dog I'I into engagement with the socket I8. It will be noticed that the spring I9 is arranged about a cylindrical reduced end 2| of the locking dog. 7

As the locking dog I! is guided for reciprocation coaxially of the sleeve, when the socket I8 registers therewith the spring I9 will normally urge the locking dog into engagement with the socket and form a driving connection between the sleeve and the hub II. As the sleeve I6 is keyed to the shaft I2, such driving engagement between the sleeve and the hub will cause the shaft I2 to be driven from the hub of the flywheel or driving member.

The sleeve I6 is formed with an annular circumscribing channel 22 within which a two-part ring 23 is loosely mounted. A trip cam 24 is secured to this ring and projects within the annular channel 22 as illustrated. At a point diametrically opposed to the cam 24 the ring is fitted with a projecting crank arm 25 to which an operating rod 26 may be connected so that the ring together with the cam 24 may be revolved in the annular 3 channel 22 relative to the sleeve I6.

It will be noticed that-the locking dog I1 is provided with a recess 21 which, when the locking dog is in its ineffective position, registers with the annular channel 22 and in effect forms a continuation thereof so that when the locking dog is in this position and in register with the cam 24 it will be held from engagement with the socket I8. However, as the hub II is continuously revolving, if the cam 24 is moved to a position where the outer face of the recess 21 of the locking dog II is no longer in engagement with the cam 24, the spring I9 will press the locking dog into engagement with the end of the hub II so that when the recess I8 aligns with the locking dogthe latter will project therein and form the driving engagement. Upon completing its revolution, however, the locking dog will again register with the cam 24 and such engagement will, due to the contour of the cam surface, move the locking dog out of engagement with the recess and interrupt the driving connection between the shaft I2 and the hub II.

In Fig. 3 I have shown the starting position of the crank arm 25 and the cam 24. In this position the locking dog is in register with the cam 24 and held out of engagement with the recess !8. By movement of the operating rod 26 in the direction of the arrow shown in Fig. 3, the cam '24 is moved out of register with the end of the locking dog I! and as the socket i8 aligns with the locking dog the latter will engage the same and form a driving connection between the hub and the driven shaft 12. When the rod 28 is released, it is automatically returned to the position shown in Fig. 3 and as the shaft I2 completes its one revolution, the outer face of the recess 2'! in the dog will engage the cam 25 and this engagement will withdraw the locking dog from engagement with the socket I8 and interrupt the driving connection.

If the rod 26 is released the cam automatically returns to the position shown in Fig. 3 to interrupt the drive after one revolution. If the rod 26 is not released it will remain in the position shown in Fig. 4 and interrupt the drive before a complete revolution has beenmade.

A clutch mechanism of the type herein disclosed enables a punch press to operate with a greater degree of safety than hithertobecause it performs but one operation and ceases and does not continue until the operator again by a positive act places it in operation.

From the foregoing it is obvious that I have provided a clutch mechanism which is rendered ineffective automatically after each revolution of the driven shaft, which clutch mechanism is comparatively simple in construction and efficient, in operation.

While I have shown the preferred form of my invention, it is to be understood that various changes may be made in its construction by those skilled in the art without departing from the spirit of the invention as defined in the appended claim.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

In combination with the hub of a flywheel, a clutch mechanism for association with said hub, said mechanism including a driven shaft arranged coaxially of the hub and adjacent thereto and concentric therewith and extending from one face of the hub, a sleeve of an external diameter substantially agreeingwith the diameter of the hub and concentrically mounted on said shaft and keyed thereto, one face of said sleeve being closely contiguous to said face of the hub, a guide formed coaxially of the hub between the exterior of the shaft and the exterior of the sleeve, 9. locking dog reciprocably mounted in said guide, the face of said hub being formed. with a socket in which said locking dog is adapted to project when the same come in register to lcck the sleeve to the hub, said sleeve having a peripheral channel formed therein, a two-part ring loosely mounted in said channel, a trip cam secured to said ring and projecting in saidchannel, said locking'dog having a recess formed therein registering with said channel when the locking dog is disengaged from said socket, said trip cam being operative to engage the recess in said clutch dog when the latter is engaged with said socket and to move said clutch dog endwise away from said hub and disengage it from said socket, said cam acting automatically after a revolution of said sleeve subsequent to the release of the clutch dog by the cam to disengage the dog from the hub.

EDWARD J. DREIS. 

